丙烯酸钠-玉米芯接枝共聚物的制备及其对Ni^(2+)的吸附机制  

Preparation of sodium acrylate-corncobs graft copolymers and its adsorption mechanism for Ni^(2+)

作　　者：陈尚龙[1,2] 唐仕荣[2] CHEN Shanglong;TANG Shirong(College of Food and Biological Engineering,Xuzhou University of Technology,Xuzhou 221018,China;Jiangsu Key Construction Laboratory of Food Resources Development and Quality Safe,Xuzhou University of Technology,Xuzhou 221018,China)

机构地区：[1]徐州工程学院食品与生物工程学院,徐州221018 [2]徐州工程学院江苏省食品资源开发与质量安全重点建设实验室,徐州221018

出　　处：《复合材料学报》2021年第6期1939-1949,共11页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(31701566)。

摘　　要：为探索利用农业废弃物玉米芯制备高效吸附材料去除水溶液中重金属离子的可行性。利用原子转移自由基聚合(ATRP)技术将大量对重金属离子具有较强亲和能力的羧基嫁接到玉米芯表面,制备出丙烯酸钠-玉米芯接枝共聚物(MC-g-PGMA-g-PAA-Na),同时采用热重、FTIR、SEM、EDS和XPS对吸附Ni^(2+)前后的吸附材料进行表征,研究其吸附机制。结果表明MC-g-PGMA-g-PAA-Na可以有效地去除水溶液中的Ni^(2+),其羧基含量达到6.02 mmol·g^(-1),是改性前的35.4倍。MC-g-PGMA-g-PAA-Na与含有Ni^(2+)溶液接触后,主要是其含有的羧基吸附了溶液中Ni^(2+),并形成了羧酸镍,吸附前后Ni^(2+)的价态没有发生变化,羧基与Ni^(2+)的配位方式主要是双齿桥式。同时MC-g-PGMA-g-PAA-Na含有的Na+全部释放到溶液中,说明该吸附过程伴有Na+与Ni^(2+)的阳离子交换。In order to explore the feasibility of preparing high-efficiency adsorption material with agricultural waste corncobs as raw material to remove heavy metal ions from aqueous solution, a large number of carboxyl groups with strong affinity for heavy metal ions were grafted onto the surface of corncobs using atom transfer radical polymerization(ATRP) technology to obtain the sodium acrylate-corncobs graft copolymers(MC-g-PGMA-g-PAA-Na).Thermogravimetry, fourier transform infrared spectroscopy(FTIR), scanning electron microscope(SEM), X-ray energy spectrum(EDS) and X-ray photoelectron spectroscopy(XPS) were used to characterize MC-g-PGMA-g-PAANa before and after adsorption of Ni^(2+) for studying its adsorption mechanism. The results show that MC-g-PGMA-gPAA-Na can effectively remove Ni^(2+) in aqueous solution. The carboxyl content in MC-g-PGMA-g-PAA-Na reaches6.02 mmol·g^(-1) and is 35.4 times that before modification. It is proved that when MC-g-PGMA-g-PAA-Na is contacted with a solution containing Ni^(2+), the carboxyl groups contained in MC-g-PGMA-g-PAA-Na act on Ni^(2+) to adsorb Ni^(2+) in the solution and form carboxylic acid nickel. The valence of Ni^(2+) do not change before and after adsorption.The coordination mode of carboxyl and Ni^(2+) is mainly a bidentate bridge. At the same time, all Na+ contained in MCg-PGMA-g-PAA-Na are released into the solution, indicating that the process of adsorption of Ni^(2+) in the solution isaccompanied by cation exchange between Na+and Ni^(2+).

关 键 词：丙烯酸钠 接枝共聚物 Ni^(2+) 吸附机制 原子转移自由基聚合 

分 类 号：TB324[一般工业技术—材料科学与工程] X52[环境科学与工程—环境工程]